Lactams such as N-methyl pyrrolidone and other pyrrolidones are conventionally produced from γ-butyrolactone and the appropriate amine. The γ-butyrolactone itself is generally produced from the hydrogenation of maleic esters in the vapour phase. The maleic esters are produced from maleic anhydride which in turn is produced from the oxidation of butane. In view of the large number of steps present, the cost of the process is high and since N-methyl pyrrolidone and other pyrrolidones are commercially important commodity chemicals it is desirable to provide a process which gives a cost-effective route to the lactam.